ABSTRACT
Department of Dermatology, School of Medicine, University of California San Francisco,
San Francisco, California, U.S.A.
INTRODUCTION
The skin forms an effective two-way barrier that controls the loss of chemicals from
the body as well as the absorption of many foreign chemicals into the body.
However, many chemicals do enter via the skin and some, when specifically
applied to the skin, have been found to be sufficiently well absorbed to produce
systemic toxicity.